Finally I have time to work on my truck. Am planning to rebuild the engine, nothing fancy just keep it basically stock performance. But i am in need of a new carb. It is a 77 f250, 460 cu.in c6 tranny. I have given thought to an edelbrock or a holley. I know holley makes one that is a 600 cfm, another that is 670 and another that is 750 cfm. I just want to match up the new one with the old. Does anyone know what cfm the orignal 4- barrel was. Any other suggestions as to brand would be great.

 

find a quadrajet, do a few simple mods and rebuild it....one of the best carbs ever designed

 

Moved to carb forum.

 

I would like some input on this too.I think the orig carb was 600cfm,I have a 84 460 rebuilt stock with a 750 holley on it now a friend of mine is a machanic that works on a vintage funny car team and he set and tuned my motor for me I never had a carbed motor run so good but he said the carb I have on there is a little big for a stock 460.I lost about 3mpg running it know matter how I drive it.Right now I am looking to put a 600 double pumper on it and let him set it up for me and see how it works out I will keep the 750 for when I put a cam and headers on it.

 

there is no reason to run a double pumper on the street. especially on a stock motor, yyour going to burn probably more gas over what you are now. and pobabaly loose your bottom end power. I would reccomend a good vaccum secondary 600 or 650 cfm carb like what came on the engine, youl get some mileage back, and some low end back.
i also highly reccomend quadrajets because of their small primaries and infininite adjustability

 

I tried to lookup the carb number according to the directions at the beginning of the carb section, but either I am blind (which could be) or my carb is not marked in that way. A friend that build and tunes stock car engines says he thinks its a 600 cfm. I think I will probably go with that. I appreaciate the input about the 750 I had considered it also and what you are saying is same thing I was told. That is that unless you are building it up a larger carb will not help and just burn more gas in the process. Kubota Orange I have had quadra Jets on several vehicles. And I agree with you that they are great for gas mileage, if they work right! I have had several professional carb tuners tell me the same thing when one works well its one of the best carb out there, but when it doesn't its a crap shoot as to whether it can be repaired or not. The motorcraft carb it came with is basically a holley. And holley makes a stock replacement carb #0-80452 with the ford automatic kickdown plate. According to them it should bolt right up. I hope! A quadrajet would take a lot of extra parts and tuning to get it right. I am not dissing the carb I just want it to work with a minumin amount of fussing. Also I believe a new one would run more $$$$ Summit racing list the holley for $279.

 

600CFM is plenty for a stock engine. I prefer the Edelbrock carbs for everyday street driving.

 

I don't want to sound stupid but why? I have decided on a 600 cfm but haven't decided on brand. I am leaning toward the holley simply because like I stated earlier it comes with basically everything I need. Just a spring kit for about 10$ is the only extra. But I sure would some input on other carbs, after all that is what this is all about. but whatever i decide i will keep you posted as to how well it works, issues,and whether I like it.

 

They give better mileage and throttle response than most Holley's will. I have both and prefer the Edelbrock over the Holley.

 

i prefer the q-jet.....i got rid of my holley street avenger and bought 5 used q-jets. I have 100 bucks in them and two good workings carbs. Most people have trouble with them because there are so many things to tune on them. idle mixture, pprimary rods, jets, primary step up spring, float level, secondary hanger, secondary metering rods, apt and the secondary air valve spring. Ohh yea the accel pump is somewhat adjustabel too.

for a motor more than stock like mine...you have to make some modifications on th elater carbs(like mine) like drilling out the idle mixture screw holes to .030 smaller than mixture needle, and possibly drilling out the idle dishcharge tubes out

my favorite part is i havent been able to stal mine out due to angles yet. The holley and edebr***** ive run couldnt go near where this carb can

 

I have a 625 afb on my 460, just love it, set and forget it. Had a holley, everytime the weather would change, up went the hood for an adjustment. Quadrajets would be too much to make work and they are bad for wearing out throttle shafts which cause leaks. Just my 2 cents

Goon

 

i agree, edelbrocks and q-jets, set and forget....but edelbrcks are terrible i mean

TERRIBLE off road. And there is no way to adjust the secondary air valves on the edelbrocks, they use counter weights

 

Personally, I have never had a problem offroad with the Carter that is on my 460, side hills, hill climbs, decents, never flooding, always good. I do agree they could have made a better secondary air valve system.

Goon

 

Well I got a 600 vac secondary electric choke holley that looks like new last night for $60.00 so even if it needs a kit I am still ahead. I rebuilt one of these once for my 79 f-250 with a mildly built 351m and it ran great but it had a manual choke so I ordered the same carb with the electric choke and installed it on the same 351 an it ran like crap nothing I did to that carb helped till the day I sold the truck and yet I put the one I rebuilt on my 70 rally sport camaro and there again motor ran flawless so I dont know if I got a lemon when I bought new or what.My mechanic buddy is also a Q-jet man but I never had any luck with the chevys they were on and now I am a ford guy(and always will be) and dont want one of those carbs near my truck LOL. On a side note I just missed a set of L&L headers for a 460 for $247.00

 

Weel I tore the motor down yesterday. I am happy to say after all this time the inside looks great. No sludge buildup anywhere but the top of the heads under the rocker arm covers. Everything came apart quite easily even the exhaust manifold bolts. Also picked up a 600 cfm holley from a local shop. $100 if I decide to keep it. It's not new but it was only used for two weeks the dude rolled his truck and totaled it. this guy nick is an old ford man from way back and will be doing my heads. He claims the holley will work and once I get the motor back together he will adjust the carb for me. If it don't work I owe him nothing. I will just have find a different carb. I figured I had nothing to lose, so why not. I will keep you posted.